JP6783257B2 - Axial rotating machine - Google Patents

Description

The present invention relates to an axial-flow rotating machine.

Conventionally, axial-flow rotating machines such as steam turbines and gas turbines used in power plants and the like are known. This axial-flow rotating machine has a nozzle structure supported by a casing and a moving blade provided on the downstream side of the nozzle structure and supported by a turbine rotor (hereinafter, simply referred to as a rotor) that is rotatable with respect to the casing. It has a structure and a stationary blade structure provided on the downstream side of the moving blade structure and supported by a casing, and the energy of the working fluid flowing from the upstream to the downstream in the axial direction of the rotor is used as the rotational energy of the rotor. It is designed to be converted.

In the above axial flow rotating machine, in the seal portion that seals between the rotor or rotor blade structure and the casing, the working fluid deviating from the main flow path flows in while having the swirling flow component given when it passes through the nozzle. It is known that a swirling flow (so-called swirl flow) is generated in the circumferential direction of the rotor. When the rotor is eccentric due to the swirl flow, a sinusoidal pressure distribution having a peak in a direction different from the eccentric direction of the rotor is generated in the circumferential direction of the rotor. For example, the swirl flow increases with high output operation. In some cases, it may cause self-excited vibration of the rotor. For this reason, various structures for suppressing or preventing the swirl flow in the seal portion have been devised. For example, in Patent Document 1, an angle such that the direction of the swirl flow in the circumferential direction is reversed toward the inlet side of the labyrinth seal. A configuration in which a swirl breaker having the above is attached is disclosed.

U.S. Pat. No. 4,420,161

Here, the movement of the swirl flow in the cavity (seal inlet) outside the mainstream in the radial direction is complicated, and according to the diligent research of the present inventors, the swirl flow does not merely go in the circumferential direction of the rotor. , It turned out that it is a spiral flow that draws a spiral in three dimensions while heading in the circumferential direction. That is, the swirl flow flows in the circumferential direction (rotational direction) of the rotor with three-dimensional spiral movement in the radial direction and the axial direction of the rotor. For this reason, even if a swirl breaker having an angle that reverses the direction of the swirl flow in the circumferential direction is simply placed on the inlet side of the labyrinth seal, it cannot be said that the swirl flow is effectively suppressed, and further. There was a need for improvement.

At least some embodiments of the present invention aim to prevent or suppress swirl flow in an axial-flow rotating machine.

(1) The axial-flow rotating machine according to at least one embodiment of the present disclosure is
A rotor that rotates around the axis and
A casing that rotatably accommodates the rotor and
A stationary blade stage including a plurality of stationary blades fixed to the casing at intervals in the circumferential direction, and an inner peripheral side stationary blade ring connected to the inner peripheral side end of each of the plurality of stationary blades.
A rotor blade stage including a plurality of rotor blades fixed to the rotor at intervals in the circumferential direction, and an outer peripheral rotor blade ring connected to the outer peripheral end of each of the plurality of rotor blades.
A rotor blade side sealing device for sealing between the outer peripheral rotor blade ring and the casing is provided.
The moving blade side sealing device is
An annular seal fin extending from the casing toward the outer peripheral surface of the outer peripheral blade ring,
A swirl breaker fixed to the casing in a cavity formed on the upstream side of the seal fin.
The swirl breaker
A first plate-shaped member having a surface along the radial direction of the rotor, and on the axis so that the upstream edge of the first plate-shaped member is located on the upstream side in the rotational direction of the rotor with respect to the downstream edge. Includes a first plate-like member that extends in the direction of intersection.

During the operation of an axial-flow rotating machine, a so-called swirl flow is generated in which the working fluid deviating from the main flow path flows in the circumferential direction as the rotor rotates, and a sinusoidal shape having a peak around the axis in a direction different from the eccentric direction of the rotor. Pressure distribution can occur. Due to the seal excitation force based on this pressure distribution, a fluid force acts on the rotor in the direction perpendicular to the eccentric direction (the direction that promotes swinging) at the seal portion between the moving blade stage and the casing, and the rotor Self-excited vibration can occur. A swirl breaker is used to suppress such vibration, but the swirl flow in the cavity is complicated, and the effect of the swirl breaker cannot be sufficiently obtained unless it is properly arranged.
In this regard, according to the configuration of (1) above, the first plate-shaped member of the swirl breaker fixed to the casing on the upstream side of the seal fin has a surface along the radial direction of the rotor, and the upstream edge is downstream. It is arranged so as to be located upstream of the edge in the rotation direction of the rotor. That is, the first plate-shaped member is a swirl flow that flows upstream of the seal fin in the circumferential direction of the rotor, and is orthogonal to at least a part of the swirl flow that spirally swirls around the circumferential direction of the rotor. Can be arranged, so that the swirl flow can be effectively suppressed.

(2) In some embodiments, in the configuration described in (1) above,
The swirl breaker
A second plate-shaped member and a third plate-shaped member having a surface inclined with respect to the radial direction of the rotor and extending from the inner end of the first plate-shaped member toward the downstream side in the rotation direction of the rotor. A second plate-shaped member, and a third plate-shaped member extending from the inner end of the first plate-shaped member toward the upstream side in the rotational direction of the rotor on the upstream side of the second plate-shaped member. Including further.

According to the configuration of (2) above, the second plate-shaped member extending from the inner end of the first plate-shaped member toward the downstream side in the rotation direction of the rotor via the first plate-shaped member and the same inside. A third plate-like member extending from the end toward the upstream side in the rotation direction of the rotor allows the swirl flow to spiral in the circumferential direction of the rotor to be orthogonal to the swirl flow at different positions in the circumferential direction. A swirl breaker can be placed. Therefore, the swirl flow can be suppressed more effectively and the occurrence of unstable vibration can be prevented.

(3) In some embodiments, in the configuration described in either (1) or (2) above,
The intersection angle between the extending direction of the first plate-shaped member and the axis is 30 ° or more and 60 ° or less.

As a result of diligent research by the present inventors, it has been found that the speed of the swirl flow in the seal fin can be significantly suppressed by arranging the first plate-shaped member at an inclination angle of 30 to 60 ° with respect to the axis of the rotor. did. That is, in the radial direction of the rotor, the swirl flow is generated when the intersection angle on the acute angle side formed by the line connecting the upstream edge and the downstream edge of the first plate-shaped member and the axis of the rotor is 30 ° or more and 60 ° or less. Can be effectively suppressed. Therefore, according to the configuration (3) above, since the first plate-shaped member is arranged at an inclination angle of 30 to 60 ° with respect to the axis line, it is possible to obtain an axial flow rotating machine capable of appropriately suppressing the swirl flow. it can.

(4) The axial-flow rotating machine according to at least one embodiment of the present disclosure is
A rotor that rotates around the axis and
A casing that rotatably accommodates the rotor and
A stationary blade stage including a plurality of stationary blades fixed to the casing at intervals in the circumferential direction, and an inner peripheral side stationary blade ring connected to the inner peripheral side end of each of the plurality of stationary blades.
A rotor blade stage including a plurality of rotor blades fixed to the rotor at intervals in the circumferential direction, and an outer peripheral rotor blade ring connected to the outer peripheral end of each of the plurality of rotor blades.
A rotor blade side sealing device for sealing between the outer peripheral rotor blade ring and the casing is provided.
The moving blade side sealing device is
An annular seal fin extending from the casing toward the outer peripheral surface of the outer peripheral blade ring,
A swirl breaker fixed to the casing in a cavity formed on the upstream side of the seal fin.
The swirl breaker
A first plate-shaped member having a surface along the radial direction of the rotor, and a first plate-shaped member extending along the axis, and
A second plate-shaped member or a third plate-shaped member having a surface inclined with respect to the radial direction of the rotor, extending from the inner end of the first plate-shaped member toward the downstream side in the rotation direction of the rotor. An existing second plate-shaped member, or a third plate-shaped member extending from the inner end of the first plate-shaped member toward the upstream side in the rotational direction of the rotor on the upstream side of the second plate-shaped member. including.

According to the configuration of (4) above, in the swirl breaker fixed to the casing on the upstream side of the seal fin, the first plate-shaped member has a surface along the radial direction of the rotor and is arranged along the axial direction. The second plate-shaped member extends from the inner end of the first plate-shaped member toward the downstream side in the rotational direction of the rotor via the first plate-shaped member. Alternatively, the third plate-shaped member extends from the inner end of the first plate-shaped member toward the upstream side in the rotation direction of the rotor. That is, since the swirl breaker can be arranged so as to be orthogonal to the swirl flow that flows while drawing a spiral with respect to the circumferential direction of the rotor at any different positions in the axial direction and the circumferential direction, the swirl flow is effective. It is possible to prevent the occurrence of unstable vibration.

(5) In some embodiments, in the configuration described in (4) above,
The swirl breaker
The first plate-shaped member, the second plate-shaped member, and the third plate-shaped member are included.

According to the configuration of (5) above, the swirl breaker is arranged so as to be orthogonal to the swirl flow flowing while drawing a spiral with respect to the circumferential direction of the rotor at a plurality of different positions in the axial direction and the circumferential direction of the rotor. Therefore, the swirl flow can be suppressed more effectively and the occurrence of unstable vibration can be prevented.

(6) In some embodiments, in the configuration described in any one of (3) and (5) above,
The swirl breaker consists of a single plate member.
The second plate-shaped member and the third plate-shaped member are configured to be bendable with respect to the first plate-shaped member independently of each other.
At the inner end of the first plate-shaped member, a first bent portion for extending the second plate-shaped member toward the downstream side in the rotational direction of the rotor, and the third plate-shaped member of the rotor. A second bent portion is formed so as to extend toward the upstream side in the rotation direction.

According to the configuration of (6) above, a swirl breaker including the first plate-shaped member, the second plate-shaped member, and the third plate-shaped member can be integrally formed by one plate member. The second plate-shaped member extends toward the downstream side in the rotational direction of the rotor via the first bent portion without affecting the third plate-shaped member. The other third plate-shaped member extends toward the upstream side in the rotational direction of the rotor via the second bent portion without affecting the second plate-shaped member. Therefore, an axial-flow rotating machine that achieves the effect described in any one of (3) and (5) above can be easily realized with a simple configuration. In such a swirl breaker, for example, one plate member is prepared, the second plate-shaped member is bent to the downstream side, which is one of the rotation directions of the rotor, via the first bent portion, and the third plate-shaped member is bent. Can be formed by bending to the upstream side, which is the other side of the rotation direction of the rotor. Therefore, it is possible to obtain an axial-flow rotating machine that has improved workability and is easy to assemble.

(7) In some embodiments, in the configuration described in any one of (2) to (6) above,
The second plate-shaped member extends so that the distance from the inner end of the first plate-shaped member to the downstream side in the rotational direction of the rotor becomes longer toward the downstream side of the axis.
The third plate-shaped member is formed so as to extend toward the upstream side of the axis so that the distance from the inner end of the first plate-shaped member to the upstream side in the rotational direction of the rotor becomes longer.

A swirl flow collides with the second plate-shaped member located downstream of the third plate-shaped member in the axial direction and the rotational direction of the rotor, respectively, from the inside to the outside in the upstream side and the radial direction. Therefore, it is considered that most of the swirl flow that collides with the second plate-shaped member flows to the downstream side in the axial direction and the downstream side in the rotational direction. On the other hand, the swirl flow collides with the third plate-shaped member from the downstream side in the axial direction of the rotor, the upstream side in the rotation direction, and the outside in the radial direction to the inside. Therefore, it is considered that most of the swirl flow that collides with the third plate-shaped member flows to the upstream side in the axial direction, and a flow component toward the upstream side in the rotational direction is generated due to the presence of the first plate-shaped member or the like.
In this regard, according to the configuration of (7) above, the second plate-shaped member extends to the downstream side in the rotation direction of the rotor toward the downstream side in the axial direction of the rotor, and the third plate-shaped member extends toward the upstream side in the axial direction of the rotor. The swirl breaker can be configured so that it can be appropriately orthogonal to the swirl flow that swirls around the circumferential direction of the rotor even in a small area due to the configuration that extends to the upstream side in the rotation direction of the rotor. , Can block the swirl flow.

(8) In some embodiments, in the configuration described in any one of (1) to (7) above,
On the upstream side of the seal fin, an annular downstream guide member extending from the casing toward the inside in the radial direction of the rotor is further provided.
The upstream side surface of the downstream guide member is curved so that the length of the downstream guide member along the radial direction gradually decreases toward the upstream side in the axial direction and becomes concave toward the cavity. It is formed in a shape.

According to the configuration (8) above, the upstream side surface of the downstream guide member can guide the working fluid deviating from the main flow path to the upstream side of the axis as it goes outward in the radial direction. That is, since the swirl flow can be guided to rotate around the circumferential direction of the rotor, it assists the swirl breaker of the present disclosure to be arranged so as to be orthogonal to at least a part of the swirl flow, and the swirl flow. Can be effectively suppressed.

(9) In some embodiments, in the configuration described in any one of (8) above,
On the upstream side of the downstream guide member, an annular upstream guide member extending from the casing toward the inside in the radial direction of the rotor is further provided.
The downstream side surface of the upstream guide portion is curved so that the length of the upstream guide member along the radial direction of the rotor gradually decreases toward the downstream side in the axial direction and becomes concave toward the cavity. It is formed in a shape.

According to the configuration of (9) above, the downstream side surface of the upstream side guide member deviates from the main flow path and guides the working fluid to the upstream side surface of the seal fin and the inner circumference of the casing and guided to the upstream side of the axis line. It can be guided inward in the radial direction toward the upstream side of the axis. That is, since the swirl flow can be guided to rotate around the circumferential direction of the rotor, it assists the swirl breaker of the present disclosure to be arranged so as to be orthogonal to at least a part of the swirl flow, and the swirl flow. Can be effectively suppressed.

(10) In some embodiments, in the configuration described in any one of (1) to (9) above,
On the upstream side of the seal fin, an annular stator-side guide member extending from the casing toward the inside in the radial direction of the rotor is further provided.
The upstream side surface of the stator side guide member is
A proximal side surface extending along the radial direction of the rotor and
It is a tip side surface connected to the inside of the base end side surface in the radial direction, and the length of the stator side guide portion along the radial direction of the rotor gradually decreases toward the upstream side in the axial direction. , And a curved tip side surface that is concave toward the cavity.

According to the configuration of (10) above, the curved tip side surface provided on the stator side guide member allows the working fluid that deviates from the main flow path and reaches the outer periphery of the outer peripheral side rotor blade ring in the radial direction with the seal fin. The vortex can be efficiently generated by turning toward the outer circumference of the outer peripheral blade ring on the upstream side of the above. As a result, it is possible to reduce leakage of the working fluid toward the downstream side of the axis through the gap between the seal fin and the outer peripheral side rotor blade ring, so that the sealing function can be maintained or improved.

(11) In some embodiments, in the configuration described in (10) above,
An annular rotor-side guide member extending from the outer peripheral surface of the outer peripheral blade ring toward the outside in the radial direction of the rotor is further provided on the upstream side of the stator-side guide member.
The downstream side surface of the rotor side guide member is gradually reduced in length along the radial direction of the rotor side guide portion toward the downstream side in the axial direction, and the front end side surface of the stator side guide member. It is formed in a curved shape that becomes concave toward.

According to the configuration (11) above, the rotor side guide member allows the working fluid that deviates from the main flow path and reaches the outer side in the radial direction along the upstream side surface of the outer peripheral side rotor blade ring on the outer peripheral side on the upstream side of the seal fin. The vortex can be efficiently generated by turning toward the outer circumference of the rotor blade ring. As a result, it is possible to reduce leakage of the working fluid toward the downstream side of the axis through the gap between the seal fin and the outer peripheral side rotor blade ring, so that the sealing function can be maintained or improved.

(12) The axial-flow rotating machine according to at least one embodiment of the present disclosure is
A rotor that rotates around the axis and
A casing that rotatably accommodates the rotor and
A stationary blade stage including a plurality of stationary blades fixed to the casing at intervals in the circumferential direction, and an inner peripheral side stationary blade ring connected to the inner peripheral side end of each of the plurality of stationary blades.
A rotor blade stage including a plurality of rotor blades fixed to the rotor at intervals in the circumferential direction, and an outer peripheral rotor blade ring connected to the outer peripheral end of each of the plurality of rotor blades.
A stationary blade side sealing device for sealing between the inner peripheral side stationary blade ring and the rotor is provided.
The stationary blade side sealing device is
An annular seal fin extending from the inner peripheral surface of the inner peripheral side stationary blade ring toward the rotor, and
Including a swirl breaker fixed to the inner peripheral side stationary ring on the upstream side of the seal fin.
The swirl breaker
A first plate-shaped member having a surface along the radial direction of the rotor, and on the axis so that the upstream edge of the first plate-shaped member is located on the upstream side in the rotational direction of the rotor with respect to the downstream edge. Includes a first plate-like member that extends in the direction of intersection.

According to the configuration of (12) above, the swirl flow suppression effect in the rotor blade stage described in (1) above can be enjoyed also in the stationary blade stage. That is, the first plate-shaped member of the swirl breaker fixed to the inner peripheral side stationary ring on the upstream side of the seal fin has a surface along the radial direction of the rotor, and the upstream edge rotates the rotor more than the downstream edge. It is arranged so as to be located on the upstream side in the direction. That is, the first plate-shaped member is arranged so as to be a swirl flow flowing in the circumferential direction of the rotor on the upstream side of the seal fin and further orthogonal to at least a part of the swirl flow swirling around the circumferential direction of the rotor. Therefore, the swirl flow can be effectively suppressed.

According to some embodiments of the present invention, swirl flow can be prevented or suppressed in an axial-flow rotating machine.

It is the schematic which shows the structural example of the axial flow rotary machine which concerns on one Embodiment. It is a schematic diagram which shows typically the swirl flow generated in the cavity of the axial flow rotating machine which concerns on one Embodiment. It is a side sectional view which shows the flow of the working fluid flowing through the seal part of a moving blade and a casing. It is a schematic diagram which shows the arrangement of the swirl breaker in one Embodiment. It is a figure which shows the relationship between the mounting angle of the 1st plate-like member of a swirl breaker with respect to an axis, and the swirl speed in a seal fin. (A) is a side sectional view showing the flow of the working fluid in the cavity in one embodiment, (b) is a perspective view showing the arrangement of the swirl breaker in one embodiment, and (c) is the A direction in (b). It is a figure which shows the view and the B direction view. (A) is a side sectional view showing the flow of the working fluid in the cavity in one embodiment, (b) is a perspective view showing the arrangement of the swirl breaker in one embodiment, and (c) is the A direction in (b). It is a figure which shows the view and the B direction view. (A) is a side sectional view showing the flow of the working fluid in the cavity in one embodiment, (b) is a perspective view showing the arrangement of the swirl breaker in one embodiment, and (c) is the A direction in (b). It is a figure which shows the view and the B direction view. (A) is a side sectional view showing the flow of the working fluid in the cavity in one embodiment, (b) is a perspective view showing the arrangement of the swirl breaker in one embodiment, and (c) is the A direction in (b). It is a figure which shows the view and the B direction view. (A) is a side sectional view showing the flow of the working fluid in the cavity in one embodiment, and (b) is a side view showing the arrangement of the swirl breaker in one embodiment. (A) is a side sectional view showing the flow of the working fluid in the cavity in one embodiment, and (b) is a side view showing the arrangement of the swirl breaker in one embodiment.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in some of the embodiments shown below are not intended to limit the scope of the present invention unless otherwise specified. It is just an example of explanation.
For example, expressions that represent relative or absolute arrangements such as "in a certain direction", "along a certain direction", "parallel", "orthogonal", "center", "concentric" or "coaxial" are exact. Not only does it represent such an arrangement, but it also represents a state of relative displacement with tolerances or angles and distances to the extent that the same function can be obtained.
Further, for example, an expression representing a shape such as a quadrangular shape or a cylindrical shape not only represents a shape such as a quadrangular shape or a cylindrical shape in a geometrically strict sense, but also includes a concavo-convex portion or a concavo-convex portion within a range in which the same effect can be obtained. The shape including the chamfered portion and the like shall also be represented.
On the other hand, the expressions "equipped", "equipped", "equipped", "included", or "have" one component are not exclusive expressions that exclude the existence of other components.

FIG. 1 is a schematic view showing a configuration example of an axial-flow rotating machine according to an embodiment. FIG. 2 is a schematic view schematically showing a swirl flow generated in a cavity of an axial-flow rotating machine according to an embodiment. FIG. 3 is a side sectional view showing the flow of the working fluid flowing through the seal portion between the moving blade and the casing.

As shown in FIGS. 1 to 3, the axial-flow rotating machine 1 according to at least one embodiment of the present disclosure includes a rotor 2 that rotates around an axis X, a casing 3 that rotatably accommodates the rotor 2, and a casing 3. On the other hand, a stationary blade stage 10 including a plurality of stationary blades 11 fixed at intervals in the circumferential direction P, and an inner peripheral blade ring 12 connected to the inner peripheral side end 11A of each of the plurality of rotor blades 11. A moving blade stage including a plurality of moving blades 21 fixed to the rotor 2 at intervals in the circumferential direction P, and an outer peripheral side moving blade ring 22 connected to the outer peripheral side end 21A of each of the plurality of moving blades 21. 20, a rotor blade side sealing device 23 for sealing between the outer peripheral rotor blade ring 22 and the casing 3, and a nozzle structure 4 including at least one nozzle 4A are provided.

The axial flow rotating machine 1 according to some embodiments can be applied as, for example, an axial flow turbine such as a steam turbine or a gas turbine used in a power system of a power plant or a ship.
The rotor 2 may be connected to a power transmission system such as a generator or a ship (not shown). The rotor 2 transmits a driving force so that the rotational force of the rotor 2 can be converted into electric energy by a generator or used as a propulsive force for a ship or the like. In some embodiments, the rotor 2 may have a plurality of blades 21 fixed to it. These rotor blades 21 may be arranged radially on the outer peripheral surface of the rotor 2 at intervals along the circumferential direction of the rotor 2.

A gas or steam supply pipe (not shown) is connected to the casing 3, and the combustion gas generated in the combustor (not shown) or the steam generated in the boiler (not shown) is the working fluid. As a result, it is supplied to the axial flow rotating machine 1. The working fluid supplied to the axial-flow rotating machine 1 is guided to the most upstream turbine paragraph among the plurality of turbine paragraphs.
A plurality of nozzle structures 4 are supported on the casing 3. These nozzle structures 4 and rotor blades 21 are alternately arranged in the axial direction of the rotor 2. Then, one turbine paragraph is formed by one nozzle structure 4 and one moving blade 21 arranged adjacent to each other on the downstream side of the one nozzle structure 4. The axial flow rotating machine 1 is provided with a plurality of such turbine paragraphs in the axial direction of the rotor 2. In this way, the working fluid supplied through the gas or steam supply pipe passes through the plurality of turbine paragraphs, performs work on the rotor blades 21, and the rotor 2 is rotationally driven. Then, the working fluid that has passed through the moving blades 21 in the final paragraph is discharged to the outside of the axial-flow rotating machine 1 through the exhaust flow path.
In some embodiments, the casing 3 may include, in addition to the casing body 3A, a support 3B that supports the seal fins 24 (described below) that make up the moving blade side seal device 23 (see FIG. 1).

The rotor blade side sealing device 23 is fixed to the casing 3 in an annular seal fin 24 extending from the casing 3 toward the outer peripheral surface 22A of the outer peripheral blade ring 22 and a cavity 6 formed on the upstream side of the seal fin 24. The swirl breaker 30 is included.
The seal fins 24 are arranged on the most upstream side of one or more labyrinth seals in the moving blade side sealing device 23, and are arranged in an annular shape around the axis X. In some embodiments shown in the present disclosure, one or more labyrinth seals including the seal fin 24 prevent leakage of the working fluid between the upstream side and the downstream side of each of the rotor blade stage 20 or the stationary blade stage 10. The portion for prevention is referred to as a seal portion 8.
The swirl breaker 30 is for blocking the swirl flow S formed along the circumferential direction P of the rotor 2, and is supported by the casing 3 or the rotor 2 in the cavity 6. In some embodiments, the casing 3 may be arranged radially at intervals along the inner circumference of the casing 3.
The swirl breaker 30 in one embodiment of the present disclosure is a first plate-shaped member 31 having a surface along the radial direction D of the rotor 2, and the upstream edge 31A of the first plate-shaped member 31 is the downstream edge 31B. A first plate-shaped member 31 extending in a direction intersecting the axis X so as to be located upstream of the rotation direction R of the rotor 2 is included (see FIGS. 4 to 7).

Here, the flow of the working fluid in the axial-flow rotating machine 1 will be described.
As shown in FIGS. 1 to 4, when a working fluid such as a combustion gas generated by a combustor (not shown) or steam generated by a boiler (not shown) is supplied to the axial-flow rotating machine 1, the working fluid becomes the working fluid. The gap between the adjacent moving blades 21 and the nozzle 4A guide the rotor 2 from the upstream side to the downstream side through the main flow path M formed along the axial direction of the rotor 2. Then, the rotor 2 that receives the kinetic energy of the working fluid via the moving blade 21 rotates in the rotation direction R (see FIG. 2). Further, the working fluid on the upstream side has a higher pressure than the working fluid on the downstream side. Therefore, in the gap between the casing 3 and the outer peripheral side rotor blade ring 22, the working fluid is guided to the downstream side through the gap between at least one labyrinth seal including the seal fin 24 and the outer peripheral side rotor blade ring 22. , Returned to the main flow path M.

During the operation of the axial flow rotating machine 1, the working fluid flows in with the swirling flow component given when the working fluid passes through the nozzle, so that the working fluid flows in the rotation direction R, that is, the swirl flow S (FIG. 2). ~ 4) is formed. Similarly, in the so-called cavity 6 forming a gap between the annular recess formed on the outer periphery of the rotor 2 and the inner ring portion of the nozzle structure 4 housed in the recess, the working fluid deviated from the main flow path M swirls. A flow S can occur, resulting in a sinusoidal pressure distribution with peaks around the axis in a direction different from the eccentric direction of the rotor. Due to the seal exciting force based on this pressure distribution, self-excited vibration of the rotor 2 may occur in the seal portion 8 between the rotor blade stage 20 and the casing 3 due to the fluid force in the direction perpendicular to the eccentric direction. A swirl breaker 30 is used to suppress such vibration, but the swirl flow S in the cavity 6 is complicated, and the effect of the swirl breaker 30 cannot be sufficiently obtained unless it is arranged appropriately.
Here, according to the diligent research of the present inventors, it was found that the swirl flow S is not only toward the circumferential direction of the rotor, but also a spiral flow that draws a spiral in three dimensions while heading toward the circumferential direction. (See FIGS. 2-4 and 6 (a)). That is, the swirl flow S flows in the circumferential direction (rotational direction) of the rotor with three-dimensional spiral movement in the radial direction and the axial direction of the rotor.

FIG. 5 shows the relationship between the mounting angle of the first plate-shaped member 31 of the swirl breaker 30 with respect to the axis X and the swirl speed of the seal fin 24. The yaw angle of the swirl breaker (SB) 30 is equal to the upstream edge 31A when the upstream edge 31A of the first plate-shaped member 31 is arranged so as to be located on the upstream side of the rotation direction R of the rotor 2 with respect to the downstream edge 31B. The line connecting the downstream edge 31B is an acute-angled angle with the axis X. As can be seen from FIG. 5, the upstream edge 31A is arranged on the upstream side in the rotation direction R with respect to the downstream edge 31B, and the first plate-shaped member 31 is arranged with an appropriate yaw angle with respect to the axis X. As a result, it was found that the swirl speed in the seal fin 24 can be suppressed.
That is, according to the above configuration, the first plate-shaped member 31 of the swirl breaker 30 fixed to the casing 3 on the upstream side of the seal fin 24 has a surface along the radial direction D of the rotor 2 and has an upstream edge. Since 31A is arranged so as to be located on the upstream side of the rotation direction R of the rotor 2 with respect to the downstream edge 31B, it flows on the upstream side of the seal fin 24 in the circumferential direction P of the rotor 2, and further, the circumferential direction P of the rotor 2 Since the first plate-shaped member 31 can be arranged so as to be orthogonal to at least a part of the swirl flow S spirally swirling around the center, the swirl flow S can be effectively suppressed.

In some embodiments, the swirl breaker 30 may be arranged so that the angle of intersection between the extending direction of the first plate-shaped member 31 and the axis X is 30 ° or more and 60 ° or less. The intersection angle between the first plate-shaped member 31 and the axis X may be, for example, 45 °.
As a result of diligent research by the present inventors, by arranging the first plate-shaped member 31 at an inclination angle of 30 to 60 ° with respect to the axis X of the rotor 2, the speed of the swirl flow S in the seal fin 24 is significantly increased. It was found that it can be suppressed (see FIG. 5). That is, in the radial direction D of the rotor 2, the intersection angle on the acute angle side formed by the line connecting the upstream edge 31A and the downstream edge 31B of the first plate-shaped member 31 and the axis X of the rotor 2 is 30 ° or more and 60 °. The swirl flow S can be effectively suppressed in the following cases. Therefore, according to the above configuration, since the first plate-shaped member 31 is arranged at an inclination angle of 30 to 60 ° with respect to the axis X, it is possible to obtain an axial flow rotating machine 1 capable of appropriately suppressing the swirl flow S. it can.

7, 8 and 9, respectively, (a) is a side sectional view showing the flow of the working fluid in the cavity 6 in one embodiment, and (b) is a perspective view showing the arrangement of the swirl breaker in one embodiment. Yes, (c) is a diagram showing the A-direction view and the B-direction view in (b).
In some embodiments, the swirl breaker 30 is a second plate-like member 32 and a third plate-like member 33 having a surface inclined with respect to the radial direction D of the rotor 2 and inside the first plate-like member 31. The rotation of the rotor 2 from the inner end of the second plate-shaped member 32 extending from the end toward the downstream side in the rotation direction R of the rotor 2 and the inner end of the first plate-shaped member 31 on the upstream side of the second plate-shaped member 32. A third plate-shaped member 33, which extends toward the upstream side in the direction R, may be further included.
According to the above configuration, the second plate-shaped member 32 extends from the inner end 31C of the first plate-shaped member 31 toward the downstream side in the rotation direction R of the rotor 2 via the first plate-shaped member 31. The third plate-shaped member 33 extending from the inner end 31C toward the upstream side of the rotation direction R of the rotor 2 provides a circumference to the swirl flow S flowing while drawing a spiral with respect to the circumferential direction P of the rotor 2. The swirl breaker 30 can be arranged so that it can be orthogonal at different positions in the direction P. Therefore, the swirl flow S can be suppressed more effectively and the occurrence of unstable vibration can be prevented.

As shown in FIGS. 8 and 9, in some embodiments, the swirl breaker 30 is a first plate-like member 31 having a surface along the radial direction D of the rotor 2 and extends along the axis X. The existing first plate-shaped member 31, and the second plate-shaped member 32 or the third plate-shaped member 33 having a surface inclined with respect to the radial direction D of the rotor 2, and inside the first plate-shaped member 31. The second plate-shaped member 32 extending from the end 31C toward the downstream side in the rotation direction R of the rotor 2, or the rotor 2 from the inner end 31C of the first plate-shaped member 31 on the upstream side of the second plate-shaped member 32. The third plate-shaped member 33, which extends toward the upstream side in the rotation direction R of the above, may be included.
According to the above configuration, in the swirl breaker 30 fixed to the casing 3 on the upstream side of the seal fin 24, the first plate-shaped member 31 has a surface along the radial direction D of the rotor 2 and is along the axis X direction. The second plate-shaped member 32 extends from the inner end 31C of the first plate-shaped member 31 toward the downstream side in the rotation direction R of the rotor 2 via the first plate-shaped member 31. Alternatively, the third plate-shaped member 33 extends from the inner end 31C of the first plate-shaped member 31 toward the upstream side in the rotation direction of the rotor 2. That is, the swirl breaker 30 can be arranged so as to be orthogonal to the swirl flow S flowing while drawing a spiral with respect to the circumferential direction P of the rotor 2 at any different positions in the axial direction X direction and the circumferential direction P. Therefore, the swirl flow S can be effectively suppressed to prevent the occurrence of unstable vibration.

In some embodiments, the swirl breaker 30 may include a first plate-like member 31, a second plate-like member 32, and a third plate-like member 33. In this way, the swirl breaker 30 can be orthogonal to the swirl flow S flowing while drawing a spiral with respect to the circumferential direction P of the rotor 2 at a plurality of different positions in the axial X direction and the circumferential direction P of the rotor 2. Can be arranged, so that the swirl flow S can be suppressed more effectively and the occurrence of unstable vibration can be prevented.

As illustrated non-limitingly in FIG. 9, in some embodiments, the swirl breaker 30 comprises one plate member 30A, and the second plate-like member 32 and the third plate-like member 33 are independent of each other. The second plate-shaped member 32 is directed to the downstream side in the rotation direction R of the rotor 2 at the inner end 31C of the first plate-shaped member 31 so as to be bendable with respect to the first plate-shaped member 31. A first bent portion 32A may be formed so as to extend the third plate-shaped member 33, and a second bent portion 33A may be formed so as to extend the third plate-shaped member 33 toward the upstream side in the rotation direction R of the rotor 2.
According to the above configuration, the swirl breaker 30 including the first plate-shaped member 31, the second plate-shaped member 32, and the third plate-shaped member 33 can be integrally formed by one plate member 30A. The second plate-shaped member 32 extends toward the downstream side in the rotation direction R of the rotor 2 via the first bent portion 32A without affecting the third plate-shaped member 33. The other third plate-shaped member 33 extends toward the upstream side in the rotation direction R of the rotor 2 via the second bent portion 33A without affecting the second plate-shaped member 32. Therefore, the axial-flow rotating machine 1 that achieves the effect described in any one of the above embodiments can be easily realized with a simple configuration.
In such a swirl breaker 30, for example, one plate member 30A is prepared, a cut or a gap is formed between the second plate-shaped member 32 and the third plate-shaped member 33, and the first bent portion 32A is formed. Formed by bending the second plate-shaped member 32 to the downstream side, which is one of the rotation directions R of the rotor 2, and bending the third plate-shaped member 33 to the upstream side, which is the other of the rotation direction R of the rotor 2. Can be done. By doing so, it is possible to obtain an axial-flow rotating machine 1 that has improved workability and is easy to assemble.

As illustrated non-limitingly in FIG. 9, in some embodiments, the second plate-shaped member 32 has a rotation direction R of the rotor 2 from the inner end 31C of the first plate-shaped member 31 toward the downstream side of the axis X. The third plate-shaped member 33 extends from the inner end 31C of the first plate-shaped member 31 toward the upstream side of the rotation direction R of the rotor 2 as the distance to the downstream side of the first plate-shaped member 31 becomes longer. It may be formed so as to extend so that the distance between the two is long.
The second plate-shaped member 32, which is located downstream of the third plate-shaped member 33 in the axial X direction and the rotation direction R of the rotor 2, has a swirl flow from the inside to the outside in the same upstream side and in the radial direction D. S collides. Therefore, it is considered that most of the swirl flow S that collides with the second plate-shaped member 32 flows to the downstream side in the axis X direction and the downstream side in the rotation direction R. On the other hand, the swirl flow S collides with the third plate-shaped member 33 from the downstream side in the axis X direction of the rotor 2, the upstream side in the rotation direction R, and the outside to the inside in the radial direction D. Therefore, most of the swirl flow S that collides with the third plate-shaped member 33 flows to the upstream side in the axis X direction, and the presence of the first plate-shaped member 31 or the like causes a flow component toward the upstream side in the rotation direction R. it is conceivable that.
In this respect, according to the above configuration, the second plate-shaped member 32 extends to the downstream side of the rotation direction R of the rotor 2 toward the downstream side in the axis X direction of the rotor 2, and the third plate is toward the upstream side of the axis. Since the shape member 33 extends to the upstream side of the rotation direction R of the rotor 2, it can be appropriately orthogonal to the swirl flow S that swirls around the circumferential direction P of the rotor 2 even in a small area. The swirl breaker 30 can be configured and the swirl flow S can be blocked.

10 (a) is a side sectional view showing the flow of the working fluid in the cavity in one embodiment, and FIG. 10 (b) is a side view showing the arrangement of the swirl breaker in one embodiment.
In some embodiments, an annular downstream guide member 40 extending inward in the radial direction D of the rotor 2 from the casing 3 may be further provided on the upstream side of the seal fin 24 (FIG. 10 (FIG. 10). b) See).
The upstream side surface 41 of the downstream guide member 40 is gradually reduced in length along the radial direction D of the rotor 2 of the downstream guide member 40 toward the upstream side in the axis X direction, and is concave toward the cavity 6. It may be formed in a curved shape.
According to the above configuration, the upstream side surface 41 of the downstream guide member 40 can guide the working fluid deviating from the main flow path M toward the upstream side of the axis X as it goes outward in the radial direction D. That is, since the swirl flow S can be guided to turn around the circumferential direction P of the rotor 2, the swirl breaker 30 of the present disclosure is arranged so as to be orthogonal to at least a part of the swirl flow S. It can assist and effectively suppress the swirl flow S.

In some embodiments, an annular upstream guide member 50 extending from the casing 3 toward the inside of the rotor 2 in the radial direction D may be further provided on the upstream side of the downstream guide member 40 (FIG. 10 (b)).
The downstream side surface 51 of the upstream guide member 50 is gradually reduced in length along the radial direction D of the rotor 2 of the upstream guide member 50 toward the downstream side in the axis X direction, and is concave toward the cavity 6. It may be formed in a curved shape.
According to the above configuration, the downstream side surface 51 of the upstream side guide member 50 deviates from the main flow path M and is guided to the upstream side surface of the seal fin 24 and the inner circumference of the casing 3 and guided to the upstream side of the axis X. The fluid can be guided inward in the radial direction D toward the upstream side of the axis X. That is, since the swirl flow S can be guided to turn around the circumferential direction P of the rotor 2, the swirl breaker 30 of the present disclosure is arranged so as to be orthogonal to at least a part of the swirl flow S. It can assist and effectively suppress the swirl flow S.

FIG. 11A is a side sectional view showing the flow of the working fluid in the cavity in one embodiment, and FIG. 11B is a side view showing the arrangement of the swirl breaker in one embodiment.
In some embodiments, an annular stator-side guide member 60 extending inward from the casing 3 in the radial direction D of the rotor may be further provided on the upstream side of the seal fin 24 (FIG. 11 (b). )reference).
The upstream side surface 41 of the stator side guide member 60 is a base end side surface 61 extending along the radial direction D of the rotor 2 and a tip end side surface 62 connected to the inside of the base end side surface 61 in the radial direction D. The length of the stator side guide member 60 along the radial direction D of the rotor 2 gradually decreases toward the upstream side in the axis X direction, and the tip side surface 62 becomes concave toward the cavity 6. It may be formed to have.
According to the above configuration, the curved tip side surface 62 provided on the stator side guide member 60 allows the working fluid to deviate from the main flow path M and reach the outside in the radial direction D from the outer circumference of the outer peripheral side rotor blade ring 22. The small vortex can be efficiently generated immediately before the seal clearance by turning toward the outer periphery of the outer peripheral side rotor blade ring 22 on the upstream side of the seal fin 24. As a result, leakage can be reduced by giving a contraction effect to the flow of the working fluid toward the downstream side of the axis X through the gap between the seal fin 24 and the outer peripheral blade ring 22, so that the sealing function can be achieved. Can be maintained or improved.

In some embodiments, on the upstream side of the stator side guide member 60, an annular rotor side guide member 70 extending from the outer peripheral surface 22A of the outer peripheral side rotor blade ring 22 toward the outside in the radial direction D of the rotor 2 is provided. Further may be provided (see FIG. 11B).
The downstream side surface 71 of the rotor side guide member 70 gradually becomes smaller in length along the radial direction D of the rotor 2 of the rotor side guide member toward the downstream side in the axis X direction, and the tip side surface of the stator side guide member 60. It may be formed in a curved shape that is concave toward 62.
According to the above configuration, the working fluid deviating from the main flow path M and reaching the outer side in the radial direction D along the upstream side surface 41 of the outer peripheral side rotor blade ring 22 by the rotor side guide member 70 is on the upstream side of the seal fin 24. It is possible to efficiently generate a vortex by turning it toward the outer circumference of the outer peripheral side rotor blade ring 22. As a result, leakage of the working fluid toward the downstream side of the axis X through the gap between the seal fin 24 and the outer peripheral side rotor blade ring 22 can be reduced, so that the sealing function can be maintained or improved.
In some embodiments, the swirl breaker 30 is attached to the outer peripheral blade ring 22 from the inner peripheral end 30B of the swirl breaker 30 to the downstream end 30C of the swirl breaker 30 in a cross-sectional view including the axis X. It may include a notch 30D, which has a curved surface that is concave toward the surface (see FIG. 11B). The cutouts 30D may be arranged together with the swirl breaker 30 at intervals along the circumferential direction P, or may be provided in an annular shape along the circumferential direction P. In this way, the vortex can be efficiently generated by turning toward the outer periphery of the outer peripheral blade ring 22 on the upstream side of the seal fin 24, and the sealing function can be maintained or improved as described above. Can be planned.

In the axial flow rotating machine 1 according to at least one embodiment of the present disclosure, the rotor 2 rotating around the axis, the casing 3 rotatably accommodating the rotor 2, and the casing 3 are spaced apart from each other in the circumferential direction P. A stationary blade stage 10 including a plurality of fixed blades 11 and an inner peripheral blade ring 12 connected to the inner peripheral end 11A of each of the plurality of rotor blades 11 and a rotor blade 2 in the circumferential direction P. A rotor blade stage 20 including a plurality of rotor blades 21 fixed at intervals and an outer peripheral blade ring 22 connected to the outer peripheral side end 21A of each of the plurality of rotor blades 21 and an inner peripheral side stationary blade ring 12 A rotor blade side sealing device 13 for sealing between the rotor 2 and the rotor blade 2 may be provided. Further, the axial flow rotating machine 1 includes a nozzle structure 4 including at least one nozzle 4A.

As shown in FIGS. 1 to 3, the axial flow rotating machine 1 according to at least one embodiment of the present disclosure includes a rotor 2 that rotates around an axis X, a casing 3 that rotatably accommodates the rotor 2, and a casing 3. On the other hand, a stationary blade stage 10 including a plurality of stationary blades 11 fixed at intervals in the circumferential direction P, and an inner peripheral blade ring 12 connected to the inner peripheral side end 11A of each of the plurality of rotor blades 11. A moving blade stage including a plurality of moving blades 21 fixed to the rotor 2 at intervals in the circumferential direction P, and an outer peripheral side moving blade ring 22 connected to the outer peripheral side end 21A of each of the plurality of moving blades 21. 20 and a rotor blade side sealing device 23 that seals between the outer peripheral rotor blade ring 22 and the casing 3 are provided.

The axial flow rotating machine 1 according to some embodiments can be applied as, for example, an axial flow turbine such as a steam turbine or a gas turbine used in a power system of a power plant or a ship.
The rotor 2 may be connected to a power transmission system such as a generator or a ship (not shown). The rotor 2 transmits a driving force so that the rotational force of the rotor 2 can be converted into electric energy by a generator or used as a propulsive force for a ship or the like. In some embodiments, the rotor 2 may have a plurality of blades 21 fixed to it. These rotor blades 21 may be arranged radially on the outer peripheral surface of the rotor 2 at intervals along the circumferential direction of the rotor 2.

A gas or steam supply pipe (not shown) is connected to the casing 3, and the combustion gas generated in the combustor (not shown) or the steam generated in the boiler (not shown) is the working fluid. As a result, it is supplied to the axial flow rotating machine 1. The working fluid supplied to the axial-flow rotating machine 1 is guided to the most upstream turbine paragraph among the plurality of turbine paragraphs.
A plurality of nozzle structures 4 are supported on the casing 3. These nozzle structures 4 and rotor blades 21 are alternately arranged in the axial direction of the rotor 2. Then, one turbine paragraph is formed by one nozzle structure 4 and one moving blade 21 arranged adjacent to each other on the downstream side of the one nozzle structure 4. The axial flow rotating machine 1 is provided with a plurality of such turbine paragraphs in the axial direction of the rotor 2. In this way, the working fluid supplied through the gas or steam supply pipe passes through the plurality of turbine paragraphs, performs work on the rotor blades 21, and the rotor 2 is rotationally driven. Then, the working fluid that has passed through the moving blades 21 in the final paragraph is discharged to the outside of the axial-flow rotating machine 1 through the exhaust flow path.
In some embodiments, the casing 3 may include, in addition to the casing body 3A, a support 3B that supports the seal fins 14 (described below) that make up the moving blade side seal device 23 (see FIG. 1).

The stationary blade side sealing device 13 relates to the annular seal fin 14 extending from the inner peripheral surface of the inner peripheral side stationary blade ring 12 toward the rotor 2 and the inner peripheral side stationary blade ring 12 on the upstream side of the seal fin 14. A swirl breaker 30 fixed to the device may be included.
The seal fins 14 are arranged on the most upstream side of one or more labyrinth seals in the stationary blade side sealing device 13, and are arranged in an annular shape around the axis X.
The swirl breaker 30 is for blocking the swirl flow S formed along the circumferential direction P of the rotor 2, and is supported, for example, on the upstream side surface of the inner peripheral side stationary blade ring 12. In some embodiments, they may be radially spaced along the upstream side of the inner peripheral vane ring 12.
The swirl breaker 30 according to the embodiment of the present disclosure is a first plate-shaped member 31 having a surface along the radial direction D of the rotor 2, and the upstream edge 31A of the first plate-shaped member 31 is the downstream edge 31B. A first plate-shaped member 31 extending in a direction intersecting the axis X so as to be located on the upstream side of the rotation direction R of the rotor 2 is included.
According to the above configuration, the swirl flow suppression effect in the rotor blade stage 20 described in some of the above-described embodiments can be enjoyed in the rotor blade stage 10 as well. That is, the first plate-shaped member 31 of the swirl breaker 30 fixed to the inner peripheral side stationary blade ring 12 on the upstream side of the seal fin 14 has a surface along the radial direction D of the rotor 2 and the upstream edge 31A It is arranged so as to be located on the upstream side of the rotation direction R of the rotor 2 with respect to the downstream edge 31B. That is, the swirl flow S flowing on the upstream side of the seal fin 14 in the circumferential direction P of the rotor 2 is orthogonal to at least a part of the swirl flow S swirling around the circumferential direction P of the rotor 2. Since one plate-shaped member 31 can be arranged, the swirl flow S can be effectively suppressed.

Here, the flow of the working fluid in the axial-flow rotating machine 1 will be described.
As shown in FIGS. 1 to 4, when a working fluid such as a combustion gas generated by a combustor (not shown) or steam generated by a boiler (not shown) is supplied to the axial-flow rotating machine 1, the working fluid becomes the working fluid. The gap between the adjacent moving blades 21 and the nozzle 4A guide the rotor 2 from the upstream side to the downstream side through the main flow path M formed along the axial direction of the rotor 2. Then, the rotor 2 that receives the kinetic energy of the working fluid via the moving blade 21 rotates in the rotation direction R (see FIG. 2). Further, the working fluid on the upstream side has a higher pressure than the working fluid on the downstream side. Therefore, in the gap between the inner peripheral side stationary blade ring 12 and the rotor 2, the working fluid is guided to the downstream side through the gap between at least one labyrinth seal including the seal fin 14 and the outer peripheral surface of the rotor 2. , Returned to the main flow path M.

During the operation of the axial flow rotating machine 1, the working fluid flows in with the swirling flow component given when the working fluid passes through the nozzle, so that the working fluid flows in the rotation direction R, that is, the swirl flow S (FIG. 2). ~ 4) is formed. Similarly, in the cavity 7 of the gap between the rotor blade stage 20 and the inner peripheral side stationary ring 12, a swirl flow S is generated in the working fluid deviating from the main flow path M, and a direction different from the eccentric direction of the rotor is generated around the axis. A sinusoidal pressure distribution with peaks can occur. Due to the seal exciting force based on this pressure distribution, in the stationary blade side sealing device 13, self-excited vibration of the rotor 2 may occur due to the fluid force in the direction perpendicular to the eccentric direction. A swirl breaker 30 is used to suppress such vibration, but the swirl flow S in the cavity 6 is complicated, and the effect of the swirl breaker 30 cannot be sufficiently obtained unless it is arranged appropriately.
Here, according to the diligent research of the present inventors, it was found that the swirl flow S is not only toward the circumferential direction of the rotor, but also a spiral flow that draws a spiral in three dimensions while heading toward the circumferential direction. (See FIGS. 2-4 and 6 (a)). That is, the swirl flow S flows in the circumferential direction (rotational direction) of the rotor with three-dimensional spiral movement in the radial direction and the axial direction of the rotor.

FIG. 5 shows the relationship between the mounting angle of the first plate-shaped member 31 of the swirl breaker 30 with respect to the axis X and the swirl speed of the seal fin 14. The yaw angle of the swirl breaker (SB) 30 is equal to the upstream edge 31A when the upstream edge 31A of the first plate-shaped member 31 is arranged so as to be located on the upstream side of the rotation direction R of the rotor 2 with respect to the downstream edge 31B. The line connecting the downstream edge 31B is an acute-angled angle with the axis X. As can be seen from FIG. 5, the upstream edge 31A is arranged on the upstream side in the rotation direction R with respect to the downstream edge 31B, and the first plate-shaped member 31 is arranged with an appropriate yaw angle with respect to the axis X. As a result, it was found that the swirl speed in the seal fin 14 can be suppressed.
That is, according to the above configuration, the first plate-shaped member 31 of the swirl breaker 30 fixed to the casing 3 on the upstream side of the seal fin 14 has a surface along the radial direction D of the rotor 2 and has an upstream edge. Since 31A is arranged so as to be located on the upstream side of the rotation direction R of the rotor 2 with respect to the downstream edge 31B, the upstream side of the seal fin 14 flows in the circumferential direction P of the rotor 2, and further, the circumferential direction P of the rotor 2 is Since the first plate-shaped member 31 can be arranged so as to be orthogonal to at least a part of the swirl flow S spirally swirling around the center, the swirl flow S can be effectively suppressed.

In some embodiments, the swirl breaker 30 may be arranged so that the angle of intersection between the extending direction of the first plate-shaped member 31 and the axis X is 30 ° or more and 60 ° or less. The intersection angle between the first plate-shaped member 31 and the axis X may be, for example, 45 °.
As a result of diligent research by the present inventors, by arranging the first plate-shaped member 31 at an inclination angle of 30 to 60 ° with respect to the axis X of the rotor 2, the speed of the swirl flow S in the seal fin 14 is significantly increased. It was found that it can be suppressed (see FIG. 5). That is, in the radial direction D of the rotor 2, the intersection angle on the acute angle side formed by the line connecting the upstream edge 31A and the downstream edge 31B of the first plate-shaped member 31 and the axis X of the rotor 2 is 30 ° or more and 60 °. The swirl flow S can be effectively suppressed in the following cases. Therefore, according to the above configuration, since the first plate-shaped member 31 is arranged at an inclination angle of 30 to 60 ° with respect to the axis X, it is possible to obtain an axial flow rotating machine 1 capable of appropriately suppressing the swirl flow S. it can.

7, 8 and 9, respectively, (a) is a side sectional view showing the flow of the working fluid in the cavity in one embodiment, and (b) is a perspective view showing the arrangement of the swirl breaker in one embodiment. , (C) are diagrams showing the A-direction view and the B-direction view in (b).
In some embodiments, the swirl breaker 30 is a second plate-like member 32 and a third plate-like member 33 having a surface inclined with respect to the radial direction D of the rotor 2 and inside the first plate-like member 31. The rotation of the rotor 2 from the inner end of the second plate-shaped member 32 extending from the end toward the downstream side in the rotation direction R of the rotor 2 and the inner end of the first plate-shaped member 31 on the upstream side of the second plate-shaped member 32. A third plate-shaped member 33, which extends toward the upstream side in the direction R, may be further included.
According to the above configuration, the second plate-shaped member 32 extends from the inner end 31C of the first plate-shaped member 31 toward the downstream side in the rotation direction R of the rotor 2 via the first plate-shaped member 31. The third plate-shaped member 33 extending from the inner end 31C toward the upstream side of the rotation direction R of the rotor 2 provides a circumference to the swirl flow S flowing while drawing a spiral with respect to the circumferential direction P of the rotor 2. The swirl breaker 30 can be arranged so that it can be orthogonal at different positions in the direction P. Therefore, the swirl flow S can be suppressed more effectively and the occurrence of unstable vibration can be prevented.

As shown in FIGS. 8 and 9, in some embodiments, the swirl breaker 30 is a first plate-like member 31 having a surface along the radial direction D of the rotor 2 and extends along the axis X. The existing first plate-shaped member 31, and the second plate-shaped member 32 or the third plate-shaped member 33 having a surface inclined with respect to the radial direction D of the rotor 2, and inside the first plate-shaped member 31. The second plate-shaped member 32 extending from the end 31C toward the downstream side in the rotation direction R of the rotor 2, or the rotor 2 from the inner end 31C of the first plate-shaped member 31 on the upstream side of the second plate-shaped member 32. The third plate-shaped member 33, which extends toward the upstream side in the rotation direction R of the above, may be included.
According to the above configuration, in the swirl breaker 30 fixed to the casing 3 on the upstream side of the seal fin 14, the first plate-shaped member 31 has a surface along the radial direction D of the rotor 2 and along the axis X direction. The second plate-shaped member 32 extends from the inner end 31C of the first plate-shaped member 31 toward the downstream side in the rotation direction R of the rotor 2 via the first plate-shaped member 31. Alternatively, the third plate-shaped member 33 extends from the inner end 31C of the first plate-shaped member 31 toward the upstream side in the rotation direction of the rotor 2. That is, the swirl breaker 30 can be arranged so as to be orthogonal to the swirl flow S flowing while drawing a spiral with respect to the circumferential direction P of the rotor 2 at any different positions in the axial direction X direction and the circumferential direction P. Therefore, the swirl flow S can be effectively suppressed to prevent the occurrence of unstable vibration.

In some embodiments, the swirl breaker 30 may include a first plate-like member 31, a second plate-like member 32, and a third plate-like member 33. In this way, the swirl breaker 30 can be orthogonal to the swirl flow S flowing while drawing a spiral with respect to the circumferential direction P of the rotor 2 at a plurality of different positions in the axial X direction and the circumferential direction P of the rotor 2. Can be arranged, so that the swirl flow S can be suppressed more effectively and the occurrence of unstable vibration can be prevented.

As illustrated non-limitingly in FIG. 9, in some embodiments, the swirl breaker 30 comprises one plate member 30A, and the second plate-like member 32 and the third plate-like member 33 are independent of each other. The second plate-shaped member 32 is directed to the downstream side in the rotation direction R of the rotor 2 at the inner end 31C of the first plate-shaped member 31 so as to be flexible with respect to the first plate-shaped member 31. A first bent portion 32A may be formed so as to extend the third plate-shaped member 33, and a second bent portion 33A may be formed so as to extend the third plate-shaped member 33 toward the upstream side in the rotation direction R of the rotor 2.
According to the above configuration, the swirl breaker 30 including the first plate-shaped member 31, the second plate-shaped member 32, and the third plate-shaped member 33 can be integrally formed by one plate member 30A. The second plate-shaped member 32 extends toward the downstream side in the rotation direction R of the rotor 2 via the first bent portion 32A without affecting the third plate-shaped member 33. The other third plate-shaped member 33 extends toward the upstream side in the rotation direction R of the rotor 2 via the second bent portion 33A without affecting the second plate-shaped member 32. Therefore, the axial-flow rotating machine 1 that achieves the effect described in any one of the above embodiments can be easily realized with a simple configuration.
In such a swirl breaker 30, for example, one plate member 30A is prepared, a cut or a gap is formed between the second plate-shaped member 32 and the third plate-shaped member 33, and the first bent portion 32A is formed. Formed by bending the second plate-shaped member 32 to the downstream side, which is one of the rotation directions R of the rotor 2, and bending the third plate-shaped member 33 to the upstream side, which is the other of the rotation direction R of the rotor 2. Can be done. By doing so, it is possible to obtain an axial-flow rotating machine 1 that has improved workability and is easy to assemble.

As illustrated non-limitingly in FIG. 9, in some embodiments, the second plate-shaped member 32 has a rotation direction R of the rotor 2 from the inner end 31C of the first plate-shaped member 31 toward the downstream side of the axis X. The third plate-shaped member 33 extends from the inner end 31C of the first plate-shaped member 31 toward the upstream side of the rotation direction R of the rotor 2 as the distance to the downstream side of the first plate-shaped member 31 becomes longer. It may be formed so as to extend so that the distance between the two is long.
The second plate-shaped member 32, which is located downstream of the third plate-shaped member 33 in the axial X direction and the rotation direction R of the rotor 2, has a swirl flow from the inside to the outside in the same upstream side and in the radial direction D. S collides. Therefore, it is considered that most of the swirl flow S that collides with the second plate-shaped member 32 flows to the downstream side in the axis X direction and the downstream side in the rotation direction R. On the other hand, the swirl flow S collides with the third plate-shaped member 33 from the downstream side in the axis X direction of the rotor 2, the upstream side in the rotation direction R, and the outside to the inside in the radial direction D. Therefore, most of the swirl flow S that collides with the third plate-shaped member 33 flows to the upstream side in the axis X direction, and the presence of the first plate-shaped member 31 or the like causes a flow component toward the upstream side in the rotation direction R. it is conceivable that.
In this respect, according to the above configuration, the second plate-shaped member 32 extends to the downstream side of the rotation direction R of the rotor 2 toward the downstream side in the axis X direction of the rotor 2, and the third plate is toward the upstream side of the axis. Since the shape member 33 extends to the upstream side of the rotation direction R of the rotor 2, it can be appropriately orthogonal to the swirl flow S that swirls around the circumferential direction P of the rotor 2 even in a small area. The swirl breaker 30 can be configured and the swirl flow S can be blocked.

10 (a) is a side sectional view showing the flow of the working fluid in the cavity in one embodiment, and FIG. 10 (b) is a side view showing the arrangement of the swirl breaker in one embodiment.
In some embodiments, an annular downstream guide member 40 extending from the outer peripheral surface of the rotor 2 toward the outside in the radial direction D of the rotor 2 may be further provided on the upstream side of the seal fin 14. See FIG. 10 (b)).
The upstream side surface 41 of the downstream guide member 40 is gradually reduced in length along the radial direction D of the rotor 2 of the downstream guide member 40 toward the upstream side in the axis X direction, and is concave toward the cavity 6. It may be formed in a curved shape.
According to the above configuration, the upstream side surface 41 of the downstream guide member 40 can guide the working fluid deviating from the main flow path M toward the upstream side of the axis X as it goes outward in the radial direction D. That is, since the swirl flow S can be guided to turn around the circumferential direction P of the rotor 2, the swirl breaker 30 of the present disclosure is arranged so as to be orthogonal to at least a part of the swirl flow S. It can assist and effectively suppress the swirl flow S.

In some embodiments, an annular upstream guide member 50 extending from the rotor 2 toward the outside in the radial direction D of the rotor 2 may be further provided on the upstream side of the downstream guide member 40 (FIG. 10 (b)).
The downstream side surface 51 of the upstream guide member 50 is gradually reduced in length along the radial direction D of the rotor 2 of the upstream guide member 50 toward the downstream side in the axis X direction, and is concave toward the cavity 7. It may be formed in a curved shape.
According to the above configuration, the working fluid deviated from the main flow path M by the downstream side surface 51 of the upstream side guide member 50 and guided to the upstream side surface of the seal fin 14 and the outer periphery of the rotor 2 and guided to the upstream side of the axis X. Can be guided to the outside of the radial direction D toward the upstream side of the axis X. That is, since the swirl flow S can be guided to turn around the circumferential direction P of the rotor 2, the swirl breaker 30 of the present disclosure is arranged so as to be orthogonal to at least a part of the swirl flow S. It can assist and effectively suppress the swirl flow S.

FIG. 11A is a side sectional view showing the flow of the working fluid in the cavity in one embodiment, and FIG. 11B is a side view showing the arrangement of the swirl breaker in one embodiment.
In some embodiments, an annular stator-side guide member 60 extending from the inner peripheral vane ring 12 toward the inside of the rotor 2 in the radial direction D may be further provided on the upstream side of the seal fin 14. Good (see FIG. 11B).
The upstream side surface 41 of the stator side guide member 60 is a base end side surface 61 extending along the radial direction D of the rotor 2 and a tip end side surface 62 connected to the inside of the base end side surface 61 in the radial direction D. The length of the stator side guide member 60 along the radial direction D of the rotor 2 gradually decreases toward the upstream side in the axis X direction, and the tip side surface 62 becomes concave toward the cavity 7. It may be formed to have.
According to the above configuration, the curved tip side surface 62 provided on the stator side guide member 60 deviates from the main flow path M and reaches the inside of the inner circumference of the inner peripheral side stationary blade ring 12 in the radial direction D. The fluid can be swirled toward the inner circumference of the inner peripheral side stationary blade ring 12 on the upstream side of the seal fin 14 to efficiently generate a vortex. As a result, it is possible to reduce leakage of the working fluid toward the downstream side of the axis X through the gap between the seal fin 14 and the inner peripheral side vane ring 12, so that the seal function can be maintained or improved. ..

In some embodiments, an annular rotor-side guide member 70 extending from the outer peripheral surface 2A of the rotor 2 toward the outside in the radial direction D of the rotor 2 is further provided on the upstream side of the stator-side guide member 60. It may be (see FIG. 11 (b)).
The downstream side surface 71 of the rotor side guide member 70 gradually becomes smaller in length along the radial direction D of the rotor 2 of the rotor side guide member toward the downstream side in the axis X direction, and the tip side surface of the stator side guide member 60. It may be formed in a curved shape that is concave toward 62.
According to the above configuration, the working fluid deviating from the main flow path M and reaching the inside of the radial direction D along the upstream side surface of the inner peripheral side vane ring 12 by the rotor side guide member 70 is upstream of the seal fin 14. A small vortex can be efficiently generated immediately before the seal clearance by turning toward the inner circumference of the inner peripheral side stationary blade ring 12 on the side. As a result, leakage can be reduced by giving a contraction effect to the flow of the working fluid toward the downstream side of the axis X through the gap between the seal fin 14 and the rotor 2, so that the sealing function can be maintained or improved. Can be planned.
In some embodiments, the swirl breaker 30 is attached to the inner peripheral side stationary ring 12 from the outer peripheral end 30B of the swirl breaker 30 to the downstream end 30C of the swirl breaker 30 in a cross-sectional view including the axis X. It may include a notch 30D, which has a curved surface that is concave toward it (see FIG. 11B). The cutouts 30D may be arranged together with the swirl breaker 30 at intervals along the circumferential direction P, or may be provided in an annular shape along the circumferential direction P. In this way, the vortex can be efficiently generated by turning toward the inner circumference of the inner peripheral side stationary blade ring 12 on the upstream side of the seal fin 14, and the sealing function can be maintained or as described above. It can be improved.

According to some embodiments of the present disclosure described above, the swirl flow S can be prevented or suppressed in the axial flow rotating machine 1.

The present invention is not limited to the above-described embodiment, and includes a modified form of the above-described embodiment and a combination of these embodiments.

1 Axial flow rotating machine (axial turbine)
2 Rotor 3 Casing 3A Casing body 3B Casing support 4 Nozzle structure 6, 7 Cavity 8 Sealed part 10 Blade stage 11 Blade 11A Inner peripheral end 12 Inner peripheral blade ring 13 Blade side sealing device 14 Seal fin 20 Moving blade stage 21 Moving blade 21A Outer peripheral side end 22 Outer peripheral side moving blade ring 22A Outer peripheral surface 23 Moving blade side sealing device 24 Seal fin 30 Swirl breaker 30A Plate member 31 First plate-shaped member 31A Upstream edge 31B Downstream edge 31C Inner end 32 2 Plate-shaped member 32A 1st bent portion 33 3rd plate-shaped member 33A 2nd bent portion 40 Downstream side guide member 41 Upstream side surface 50 Upstream side guide member 51 Downstream side surface 60 Casing side guide member 61 Base end side surface 62 Tip side surface 70 Rotor Side guide member 71 Downstream side surface M Main flow path S Swirl flow X Axial direction R Rotational direction D Radial direction P Circumferential direction

Claims (10)

A rotor that rotates around the axis and
A casing that rotatably accommodates the rotor and
A stationary blade stage including a plurality of stationary blades fixed to the casing at intervals in the circumferential direction, and an inner peripheral side stationary blade ring connected to the inner peripheral side end of each of the plurality of stationary blades.
A rotor blade stage including a plurality of rotor blades fixed to the rotor at intervals in the circumferential direction, and an outer peripheral rotor blade ring connected to the outer peripheral end of each of the plurality of rotor blades.
A rotor blade side sealing device for sealing between the outer peripheral rotor blade ring and the casing is provided.
The moving blade side sealing device is
An annular seal fin extending from the casing toward the outer peripheral surface of the outer peripheral blade ring,
A swirl breaker fixed to the casing in a cavity formed on the upstream side of the seal fin.
The swirl breaker
A first plate-shaped member having a surface along the radial direction of the rotor, which extends along the axis, or the upstream edge of the first plate-shaped member is the rotation of the rotor rather than the downstream edge. A first plate-shaped member extending in a direction intersecting the axial line so as to be located upstream in the direction, and a second plate-shaped member having a surface inclined with respect to the radial direction of the rotor and a third plate-shaped member. A plate-shaped member, the second plate-shaped member extending from the inner end of the first plate-shaped member toward the downstream side in the rotational direction of the rotor, and the rotor from the inner end of the first plate-shaped member. Axial flow rotating machine including a third plate-shaped member extending toward the upstream side in the rotation direction of the above and a third plate-shaped member arranged on the upstream side of the second plate-shaped member. .. The intersection angle between the extending direction of the first plate-shaped member and the axis is 30 ° or more and 60 ° or less.
The axial-flow rotating machine according to claim 1 . The first plate-shaped member extends along the axis.
The axial-flow rotating machine according to claim 1.
The swirl breaker consists of a single plate member.
The second plate-shaped member and the third plate-shaped member are configured to be bendable with respect to the first plate-shaped member independently of each other.
At the inner end of the first plate-shaped member, a first bent portion for extending the second plate-shaped member toward the downstream side in the rotational direction of the rotor, and the third plate-shaped member of the rotor. A second bent portion is formed so as to extend toward the upstream side in the rotation direction.
The axial-flow rotating machine according to any one of claims 1 to 3 . The second plate-shaped member extends so that the distance from the inner end of the first plate-shaped member to the downstream side in the rotational direction of the rotor becomes longer toward the downstream side of the axis.
The third plate-shaped member is formed so as to extend so that the distance from the inner end of the first plate-shaped member to the upstream side in the rotational direction of the rotor becomes longer toward the upstream side of the axis.
The axial-flow rotating machine according to any one of claims 1 to 4 . A rotor that rotates around the axis and
A casing that rotatably accommodates the rotor and
A stationary blade stage including a plurality of stationary blades fixed to the casing at intervals in the circumferential direction, and an inner peripheral side stationary blade ring connected to the inner peripheral side end of each of the plurality of stationary blades.
A rotor blade stage including a plurality of rotor blades fixed to the rotor at intervals in the circumferential direction, and an outer peripheral rotor blade ring connected to the outer peripheral end of each of the plurality of rotor blades.
A rotor blade side sealing device for sealing between the outer peripheral rotor blade ring and the casing is provided.
The moving blade side sealing device is
An annular seal fin extending from the casing toward the outer peripheral surface of the outer peripheral blade ring,
A swirl breaker fixed to the casing in a cavity formed on the upstream side of the seal fin.
The swirl breaker
A first plate-shaped member having a surface along the radial direction of the rotor and extending along the axis, or the upstream edge of the first plate-shaped member is the rotation of the rotor rather than the downstream edge. A first plate-shaped member extending in a direction intersecting the axis so as to be located on the upstream side in the direction, and a second plate-shaped member or a third plate having a surface inclined with respect to the radial direction of the rotor. A plate-shaped member, the second plate-shaped member extending from the inner end of the first plate-shaped member toward the downstream side in the rotational direction of the rotor, or the rotor from the inner end of the first plate-shaped member. Including a third plate-like member, which extends toward the upstream side in the direction of rotation of the
On the upstream side of the seal fin, an annular downstream guide member extending from the casing toward the inside in the radial direction of the rotor is further provided.
The upstream side surface of the downstream guide member is curved so that the length of the downstream guide member along the radial direction gradually decreases toward the upstream side in the axial direction and becomes concave toward the cavity. Axial-flow rotating machine formed in a shape. On the upstream side of the downstream guide member, an annular upstream guide member extending from the casing toward the inside in the radial direction of the rotor is further provided.
The downstream side surface of the upstream guide member is curved so that the length of the upstream guide member along the radial direction gradually decreases toward the downstream side in the axial direction and becomes concave toward the cavity. Formed in a shape
The axial-flow rotating machine according to claim 6 . On the upstream side of the seal fin, an annular stator-side guide member extending from the casing toward the inside in the radial direction of the rotor is further provided.
The upstream side surface of the stator side guide member is
A proximal side surface extending along the radial direction of the rotor and
It is a tip side surface connected to the inside of the base end side surface in the radial direction, and the length of the stator side guide portion along the radial direction of the rotor gradually becomes smaller toward the upstream side in the axial direction. The axial-flow rotating machine according to any one of claims 1 to 7 , which is formed so as to have a curved tip side surface that is concave toward the cavity. An annular rotor-side guide member extending from the outer peripheral surface of the outer peripheral blade ring toward the outside in the radial direction of the rotor is further provided on the upstream side of the stator-side guide member.
The downstream side surface of the rotor side guide member is gradually reduced in length along the radial direction of the rotor side guide portion toward the downstream side in the axial direction, and the front end side surface of the stator side guide member. Formed in a curved shape that is concave toward
The axial-flow rotating machine according to claim 8 . A rotor that rotates around the axis and
A casing that rotatably accommodates the rotor and
A stationary blade stage including a plurality of stationary blades fixed to the casing at intervals in the circumferential direction, and an inner peripheral side stationary blade ring connected to the inner peripheral side end of each of the plurality of stationary blades.
A rotor blade stage including a plurality of rotor blades fixed to the rotor at intervals in the circumferential direction, and an outer peripheral rotor blade ring connected to the outer peripheral end of each of the plurality of rotor blades.
A stationary blade side sealing device for sealing between the inner peripheral side stationary blade ring and the rotor is provided.
The stationary blade side sealing device is
An annular seal fin extending from the inner peripheral surface of the inner peripheral side stationary blade ring toward the rotor, and
Including a swirl breaker fixed to the inner peripheral side stationary ring on the upstream side of the seal fin.
The swirl breaker
A first plate-shaped member having a surface along the radial direction of the rotor, which extends along the axis, or the upstream edge of the first plate-shaped member is the rotation of the rotor rather than the downstream edge. A first plate-shaped member extending in a direction intersecting the axial line so as to be located upstream in the direction, and a second plate-shaped member having a surface inclined with respect to the radial direction of the rotor and a third plate-shaped member. A plate-shaped member, the second plate-shaped member extending from the inner end of the first plate-shaped member toward the downstream side in the rotational direction of the rotor, and the rotor from the inner end of the first plate-shaped member. Axial flow rotating machine including a third plate-shaped member extending toward the upstream side in the rotation direction of the above and a third plate-shaped member arranged on the upstream side of the second plate-shaped member. ..

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